1—Field of the Invention
The present invention relates to plasma crucibles and to light sources that include plasma crucibles.
2—Description of Related Art
In plasma lamps a discharge is used to excite a gas in a capsule with a view to producing light. Typical examples of plasma lamps include sodium discharge lamps and fluorescent tube lamps. The fluorescent tube lamps use mercury vapor, which produces ultraviolet radiation. In turn, the ultraviolet radiation excites a fluorescent powder to produce light. Such lamps are more efficient than tungsten filament lamps in terms of lumens of light emitted per watt of electricity consumed. However, they still suffer the disadvantage of requiring electrodes within the capsule. Since the electrodes carry the current required for the discharge, they degrade and ultimately fail.